Comparative Study On RNFL Between Normal Eyes And Amblyopic Eyes In Children By OCT

Objective:To compare the thicknesses of the retinal nerve fiber layer (RNFL) in normal children and children with amblyopia by optical coherence tomography (OCT), investigating the value of differences in retinal morphology and etiology of amblyopia.Method:OCT (Carl-Zeiss Meditec, Germany) was performed on 19 normal children (38 eyes) and 88 children (176 eyes) with amblyopia to measure the thickness of RNFL from the superior, inferior, nasal and temporal quadrants in the peripapillary region. Children with amblyopia were divided into strabismus-related amblyopia, anisometropia-related amblyopia and ametropia-related amblyopia according to the type of amblyopia, while divided into mild amblyopia, moderate amblyopia and severe amblyopia according to the degree. The measured data with thickness of RNFL were analyzed by SPSS 11.0 software.Results:The chart of the thickness of RNFL was typical two-humped curve in both normal and amblyopic eyes of children. In normal eyes, the thicknesses of the global, superior, nasal, inferior and temporal quadrants of RNFL in the peripapillary region were 106.42±11.75um,132.32±10.39um,75.32±16.75um,136.37±15.53um, 81.68±17.41um, respectively. While in amblyopic eyes, the thicknesses of the global, superior, nasal, inferior and temporal quadrants of RNFL in the peripapillary region were 118.87±10.54um,146.59±17.03um 85.89±16.71um,148.34±18.74um,94.66±22.82mu, The difference between the two groups was statistically significant (p<0.05).The thicknesses of the global, superior, nasal, inferior and temporal quadrants of RNFL between the normal eyes in regular visual development children and normal eyes in children with amblyopia were not statistically significant (p>0.05).The thicknesses of the global quadrants of RNFL in the peripapillary region were 110.19±12.38um,121.89±9.03um, 120.22±8.98um in strabismus-related amblyopia, anisometropia-related amblyopia and ametropia-related amblyopia, respectively. The thicknesses of RNFL in amblyopic eyes with anisometropia-related amblyopia and ametropia-related amblyopia were more than that with strabismus-related amblyopia, and the difference was statistically significant (p<0.05).The thicknesses of the global quadrants of RNFL in the peripapillary region were 117.51±12.14um,118.99±9.60um, 120.28±9.60um in mild amblyopia, moderate amblyopia and severe amblyopia, respectively. It seemed that an increased thickness of RNFL was accompany with the degree of amblyopia, but there was no statistical difference among each groups(P>0.05).The relationship between the thickness of RNFL in amblyopic eyes and visual acuity was negative correlation though a linear correlation analysis (r=-0.353, p<0.05).Conclusion:The chart of the thickness of RNFL was typical two-humped curve in both normal and amblyopic eyes of children, with the most thickest of the superior and inferior quadrants for wave crest, and the final thin of the nasal and temporal quadrants for wave valley. From thickest to final thin of RNFL, there are successively inferior, superior, temporal and nasal quadrants.The RNFLs of the children with amblyopia were slightly thicker than that of normal children.The RNFLs of the children with anisometropia-related amblyopia and ametropia-related amblyopia were thicker than that of children with strabismus-related amblyopia.There was no statistical difference in the thickness of RNFL between normal eyes and amblyopic eyes due to strabismus.An increased thickness of RNFL in amblyopic eyes was accompany with the degree of amblyopia.